GNU versions of rcs utilities.  The Revision Control System (RCS)
manages multiple revisions of files.  RCS automates the storing,
retrieval, logging, identification, and merging of revisions.  RCS is
useful for text that is revised frequently, including source code,
programs, documentation, graphics, papers, and form letters.

Note that this port will install these utilities with a 'g' prefix,
e.g. grcs, but the documentation will refer to them without the
'g' prefix.
